The abstract service defines specific parameters for each operation. These are mapped onto corresponding parameters to each interface function, which are also called input parameters. Although each service has different parameters, some specific parameters recur in several operations and these are briefly introduced here. (For complete details of these parameters, see XDS Class Definitions.)
All parameters that are OM objects can generally be supplied to the interface functions as public objects (that is, descriptor lists) or as private objects. Private objects must be created in the workspace that is returned by ds_initialize( ). In some cases, constants can be supplied instead of OM objects.
Note: Wherever a function can accept an instance of a particular OM class as the value of a parameter, it also accepts an instance of any subclass of the OM class. For example, most functions have a name parameter, which accepts values of OM class DS_C_NAME. It is always acceptable to supply an instance of the subclass DS_C_DS_DN as the value of the parameter.
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Attribute and Attribute Value Assertion